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Main Boards => PowWow => Topic started by: fireball31 on September 30, 2016, 07:48:00 PM

Title: performance question, forgive me I am not a physics guy.
Post by: fireball31 on September 30, 2016, 07:48:00 PM
All else being equal what bow is going to be more efficient or faster. I 62 inch bow with a 17in riser or a 15in riser. Both would be drawn to 29inches.

*edited to explain say that same bow model same limb design*
Title: Re: performance question, forgive me I am not a physics guy.
Post by: on September 30, 2016, 08:05:00 PM
Idk which will be faster, but if both bows are the same length, the one with the 2" shorter riser should feel smoother because the limbs are longer.

Bisch
Title: Re: performance question, forgive me I am not a physics guy.
Post by: forestdweller on September 30, 2016, 08:17:00 PM
To my knowledge both bow's should perform the same since the limbs do all of the flexing.

The longer bow will be more stable though.
Title: Re: performance question, forgive me I am not a physics guy.
Post by: ChuckC on September 30, 2016, 08:52:00 PM
It seems the shorter how's limbs would be slightly more flexed and you would end up with a slightly different string angle.  Then, it depends on the bow and it's design.
Title: Re: performance question, forgive me I am not a physics guy.
Post by: McDave on September 30, 2016, 09:18:00 PM
I've been told that the long riser, short limbs will shoot a light arrow faster, while the short riser, long limbs, will shoot a heavier arrow faster.  I haven't tried to test this.  It sort of makes sense to me though.  A light arrow should get up to speed with a short flip, whereas a heavier arrow, with more inertia, would require a longer power stroke to get up to speed.  This might be the reason why Olympic bows have such long risers, and shoot the lightest arrows they can make work.
Title: Re: performance question, forgive me I am not a physics guy.
Post by: on September 30, 2016, 09:33:00 PM
Guys, the way I read it, both bows are 62". One with a 15" riser and one with a 17" riser. The 15" riser would have 2" longer limbs than the 17" riser.

Looks like that is the way McDave read it too, looking at his answer.

Bisch
Title: Re: performance question, forgive me I am not a physics guy.
Post by: Orion on September 30, 2016, 09:58:00 PM
Any bow that shoots a light arrow fast, will shoot a heavier arrow faster as well.

A bow really isn't the same if you change the riser length, but the longer riser will be a tad faster, with both lighter and heavier arrows, because the limbs are flexed a bit more compared to a shorter riser/longer limbs.  

Now we're not talking big differences here, maybe 1-3 FPS. It's measurable, but not noticeable to most shooters.
Title: Re: performance question, forgive me I am not a physics guy.
Post by: fireball31 on September 30, 2016, 10:22:00 PM
Bisch that is the way the question is intended. Thanks for the answers guys.
Title: Re: performance question, forgive me I am not a physics guy.
Post by: kennym on October 01, 2016, 08:02:00 AM
QuoteOriginally posted by Orion:
Any bow that shoots a light arrow fast, will shoot a heavier arrow faster as well.

A bow really isn't the same if you change the riser length, but the longer riser will be a tad faster, with both lighter and heavier arrows, because the limbs are flexed a bit more compared to a shorter riser/longer limbs.  

Now we're not talking big differences here, maybe 1-3 FPS. It's measurable, but not noticeable to most shooters.
X2

And the longer limbs "may" shoot better for you at 29" DL....